Silicon steel is a soft magnetic material with excellent magnetic property and is widely used in the production of various industrial products and household appliances. However, the production process for the silicon steel is rather complicated and difficult. In particular, fracture of high-silicon strip steel during cold-rolling process is always a difficult problem for various steelworks. With an increase of Si content, the alloy yield limit, strength limit and hardness of the material all increase, meanwhile, the material becomes more brittle and its ductility decreases, and all these bring about difficulties for rolling process for high-silicon materials.
Before in-situ cold-rolling process, oriented silicon steel and high-grade non-oriented silicon steel are required to undergo a preheating procedure. Because of reasons such as rolling pace, heat dissipation, cooling, etc., the temperature of a part of the head portion and the tail portion of the strip steel is often somewhat lower than its middle portion, so that rolling stability is poor, and fracture occurs regularly during cold-rolling (especially for the head portion and tail portion of a strip steel, as the fracture times of the head portion and tail portion of the strip steel amount to 70% of total fracture times), and thus production efficiency and equipment safety are seriously affected.